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The results of testing the algorithms of the adaptive model of a synchronous generator using theoretical and real physical data are presented in this study. The adaptive model of a synchronous machine is an equations system, which describes both the static and transient operation of a generator. Parameters of the adaptive model are found using measurements of a generator’s operational parameters. The single-machine model was created in Matlab/Simulink software to test the theoretical data. This single-machine model consists of a synchronous generator, a step-up transformer, and a transmission line. The test model also includes models of the automatic voltage regulator and steam turbine governor. The real electrodynamic model was used to verify the adaptive model of a synchronous machine. It consisted of four synchronous generators, with values of power capacity of 5 kW and 15 kW. The data logger with a sampling rate of 57.8 kHz was developed and installed to measure the operating parameters of each generator. As a result of testing on both models, the following values were estimated: inertia moment, d-axis and q-axis reactance, and load angle. These values were compared with the reference values. The adaptive model of a synchronous machine can be used in systems of emergency control and assessment of generator state.

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Large-scale centralized power systems interconnected by weak tie-lines is a typical feature of the state-of-the-industry power engineering. Another trend is distributed generation units integration with the resulting decrease of power system inertia constant and increasing sensitivity to small disturbances. In particular, in the case of significant power imbalance, periodic low-frequency oscillations of power system performance parameters may arise. Lowfrequency oscillations in power systems are inherently non-linear and nonstationary processes representing a superposition of numerous rotating masses movement components having mutual influence in a power region or power center. These situations imply the crucial role of monitoring each generator damping capability which is determined by the adjustment of the system regulators in use.To estimate the synchronous generator capability to maintain synchronous operation under deviating frequency and load angle conditions synchronizing torque and corresponding synchronizing power are proposed to be used. The possibility to determine the synchronous machine synchronizing power is subject to the presence of the load angle variation data with the techniques for defining load angle without direct measurement using a system of assumptions have been analyzed. Numerous simulations have shown that the effect of assumptions can be evaluated as acceptable.The main focus of the paper is the analysis of synchronizing power corresponding to the actual generator involved in the oscillations which had arisen after a disturbance in the Unified Energy System of Russia. The supposed cause of the oscillations is improper automatic excitation controller operation.